Name the molecules used for gluconeogenesis. What are the sources of these molecules? Under what conditions would gluconeogenesis occur?

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Hello, everyone. And welcome back. Our next question says which of the following statement or statements regarding the molecules used for gluconeogenesis is correct. We have four statements numbered one through four. And our answer choices are a two only B two and four C four only or D one and two. So we can see right away that there is no answer choice in which statement three is an option. So we don't even need to evaluate statement three. We can just cross it right off. It'll just save us a little time there if we're on a test. So let's think about gluconeogenesis and then work our way through these statements. This is a process that synthesizes glucose from non carbohydrate sources. And it's an alternate pathway sort of a lass dich resort when there's no glucose coming in through the diet and no dietary glucose and no more glycogen left to break down for glucose. It's really important for the body to maintain its proper level of blood glucose. So this is the backup system if carbohydrate sources have run out. So with that in mind, let's evaluate our statements. Statement. One says the primary substrate for gluco neogenesis is glucose obtained from dietary sources which is then converted back into glucose for storage. Well, I think you can pretty easily rule this one out. As we said, this is glucose synthesized from non-carbohydrate sources. And the substrate is then other molecules, non carbohydrate molecules lactate, pyruvate and amino acids. And these substrates are converted not back into but into glucose for immediate use. So this is when the body doesn't have access to abundant sources of glucose. And so the body needs that glucose right away to maintain glucose homeostasis. So we've ruled out statement one, which was also rules out choice D one and two. Steven two says gluconeogenesis is predominantly active during the fed state when glucose levels are high to further increase blood glucose. Well, again, previous discussion should let you rule that out pretty easily. It would be predominantly active during the fasting state or when eating a low carbohydrate diet when glucose levels are low. And it is to increase blood sugar but not further increase blood glucose. It's to prevent it from getting too low due to the lack of other sources of glucose. And actually, we didn't even need to go through that because we know choice three can't be correct, but we're in a practice problem here. So we do want to be thorough. So we notice by elimination since statement two is incorrect, then A and B two only and two and four are incorrect. So, statement four. And then thus choice C four only must be our answer. Again, we'll be thorough here and just go over statement. Four amino acids are key substrates in gluconeogenesis helping to produce glucose when carbohydrate is intake is low. And this is correct. We know it kicks into a place when there's low carbohydrate intake. And we discussed that amino acids are a substrate for gluco genesis. And this makes sense because they would be the products of the breakdown of proteins. So the body's been deprived of carbohydrates to break down for glucose. It can turn to proteins as an alternative source. So statement four is correct and our answer here is that our correct statement about the molecules that are used in gluconeogenesis is choice C statement four only see you in the next video.

Name the molecules used for gluconeogenesis. What are the sources of these molecules? Under what conditions would gluconeogenesis occur?

Verified video answer for a similar problem:

Key Concepts

Gluconeogenesis

Precursors for Gluconeogenesis

Regulation and Conditions for Gluconeogenesis